WASHINGTON, April 19 (Reuters) - Secretary of State Mike Pompeo said U.S. diplomatic efforts will continue toward the goal of denuclearization of North Korea, a day after a North Korean official said it no longer wanted to deal with him in talks.

"Nothing has changed. We'll continue to work to negotiate; still in charge of the team. President Trump's obviously in charge of the overall effort, but it'll be my team," Pompeo told reporters in Washington.

He added that U.S. diplomats led by Special Representative for North Korea Stephen Biegun would continue efforts to achieve North Korea's denuclearization, which he said North Korean leader Kim Jong Un committed to last June.

"I am convinced we will have a real opportunity to achieve that outcome," Pompeo said at a joint news conference after talks with Japan's foreign and defense ministers.

In answer to a question, Pompeo said he believed it was possible to maintain diplomatic engagement with North Korea even without providing the sanctions relief it had been demanding.

"We will continue to press North Korea to abandon all of its weapons of mass destruction, ballistic missiles related programs and facilities," Pompeo said. "We will continue to enforce all sanctions on North Korea and encourage every country to do so."

Despite Pompeo's comments, the future of U.S. engagement with North Korea has appeared to be in limbo since the summit, with no sign of direct contact between the two sides.

On Thursday, the North Korean foreign ministry official in charge of U.S. affairs said North Korea no longer wanted to deal with Pompeo and he should be replaced in talks by someone more mature.

That statement came hours after North Korea announced its first weapons test since a second summit between Trump and Kim broke down in February.

Experts said the North Korean statement appeared aimed at dividing Trump from senior officials in the hope of exacting concessions, particularly relief from punishing sanctions.

U.S. officials have played down the test of what North Korea has described as a "tactical" weapon, implying a short-range system rather than the ballistic missiles seen as a threat to the United States.

"I don't have the details; I just haven't been chasing it, there's been a few other priorities, so that'd give you kind of a sense of where it ranks," acting U.S. Defense Secretary Patrick Shanahan said before talks at the Pentagon with his Japanese counterpart Takeshi Iwaya.

Kim warned last week that the summit breakdown risked reviving tensions and said he was only interested in meeting Trump again if Washington showed more flexibility. He gave a year-end deadline for a change in attitude.

Trump has said he is open to another summit with Kim, but his national security adviser, John Bolton, told Bloomberg News on Wednesday there first needed to be "a real indication from North Korea that they've made the strategic decision to give up nuclear weapons."

In a separate development, U.S. authorities on Thursday arrested a former U.S. Marine who is a member of a group that allegedly raided the North Korean embassy in Madrid in February, two sources familiar with the arrest said.

Armed U.S. federal agents also raided the apartment of Adrian Hong, leader of Cheolima Civil Defense, a group seeking the overthrow of Kim that is blamed for the Feb. 22 raid, a person close to the group said.

Earlier this month, North Korea's foreign ministry denounced the incident a "grave terrorist attack" and cited rumors that the FBI was partially behind the raid. The U.S. State Department has said Washington had nothing to do with it. (Reporting by David Brunnstrom and Doina Chiacu; additional reporting by Phil Stewart; Editing by Marguerita Choy and Diane Craft)